Blood flow control to the brain throughout a resistance training intervention in women
| ISRCTN | ISRCTN38725877 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN38725877 |
- Submission date
- 22/07/2025
- Registration date
- 29/07/2025
- Last edited
- 29/07/2025
- Recruitment status
- Recruiting
- Overall study status
- Ongoing
- Condition category
- Circulatory System
Plain English summary of protocol
Background and study aims
This study is exploring how different types of resistance training (like lifting weights) might affect blood flow to the brain. Past research suggests that people who regularly do resistance training may experience changes in their blood vessels, which could influence how blood flows in the brain. The researchers want to compare two types of training: one using heavy weights with fewer repetitions, and another using lighter weights with more repetitions. They’ll use imaging tools to measure brain blood flow before, during, and after the training.
Who can participate?
The study is looking for young, healthy women who meet certain health and fitness criteria. There are some medical conditions and medications that would prevent someone from taking part, to ensure safety.
What does the study involve?
Participants will be assigned to one of two resistance training programs. They’ll have their brain blood flow measured using imaging tools at three points: before training starts, during the training period, and two weeks after the training ends. All exercise sessions will be supervised to ensure safety.
What are the possible benefits and risks of participating?
There are some small risks related to physical activity, but these will be minimized through health screenings and supervision. A possible benefit is that participants may develop healthy exercise habits that continue after the study ends.
Where is the study run from?
McMaster University (Canada)
When is the study starting and how long is it expected to run for?
September 2024 to May 2026
Who is funding the study?
The study is funded by the Natural Sciences and Engineering Research Council of Canada (NSERC).
Who is the main contact?
Lead student investigator, Vanessa Mizzi, mizziv@mcmaster.ca
Lead principal investigator, Dr Baraa Al-Khazraji, alkhazrb@mcmaster.ca
Contact information
Scientific, Principal Investigator
1280 Main St W
Hamilton
L8S 4L8
Canada
 ORCID ID |
0000-0003-1075-4183 |
|---|---|
| Phone | +1 9055259140 |
| alkhazrb@mcmaster.ca |
Public
1280 Main St W
Hamilton
L8S 4L8
Canada
| ORCID ID |
0009-0006-9483-0364 |
|---|---|
| Phone | +1 9055259140 |
| mizziv@mcmaster.ca |
Study information
| Study design | Single-centre interventional randomized controlled trial |
|---|---|
| Primary study design | Interventional |
| Secondary study design | Randomised controlled trial |
| Study setting(s) | University/medical school/dental school |
| Study type | Treatment |
| Participant information sheet | Not available in web format. Please use contact details to request a participant information sheet. |
| Scientific title | Cerebral blood flow control in women during a ten week, two paradigm resistance training intervention |
| Study acronym | CCRE |
| Study objectives | Although studies have shown that resistance exercise affects the vasculature, the time course of cerebrovascular adaptations throughout a resistance exercise training intervention and following cessation of resistance exercise (i.e., detraining) is unknown. As well, it remains unknown whether resistance exercise intensity influences cerebral blood flow control and effects of detraining on cerebral blood flow control. This study aims to investigate the effect of two resistance training paradigms (low load vs high load) on cerebral blood flow control over the course of a ten-week intervention and two weeks post-training cessation (i.e., detraining) in women. It is hypothesized that cerebral blood flow control will improve over the course of the resistance training intervention. It is also hypothesized that after training cessation, vascular adaptations would trend towards pre-intervention levels. Lastly, it is hypothesized that the females undergoing lower load or higher load groups would show similar cerebral blood flow control since both groups are training to volitional failure. |
| Ethics approval(s) |
Approved 21/04/2025, Hamilton Integrated Research Ethics Board (237 Barton Street East, Hamilton, L8L 2X2, Canada; +1 9055212100; eREBHelpdesk@hhsc.ca), ref: 18711 |
| Health condition(s) or problem(s) studied | Studying cerebrovascular health in relation to resistance exercise in young, healthy women |
| Intervention | This is a randomized control trial that evaluates cerebral blood flow control during a ten-week resistance training intervention. Participants will be randomized to either a heavy-lifting group (able to perform 8-12 repetitions /set to volitional failure) or a light-lifting group (able to perform 15-25 repetitions/set to volitional failure). They will perform 10 weeks of resistance exercise training, training twice weekly. They will also be asked to cease training for two weeks post intervention, to assess detraining effects. The researchers will take various measurements vascular characteristics and the cerebral-pressure flow relationship pre-intervention, throughout the intervention, and post- intervention. The randomisation process for the intervention was completed using an online tool (www.sealedenvelope.com). We used the block randomisation feature to ensure balanced allocation across groups. The system generated the randomisation codes, which were then used to assign participants accordingly. |
| Intervention type | Behavioural |
| Primary outcome measure | Cerebral-pressure flow relationship measured using a continuous blood pressure finger cuff and a transcranial doppler ultrasound at weeks 1-10, 12 during the leg press set. |
| Secondary outcome measures | 1. Cerebrovascular reactivity measured using the Douglas bag at weeks 1-10, 12 2. Vascular characteristics (pulse wave velocity, distensibility, global cerebral blood flow, flow mediated dilation) using tonometers and Duplex ultrasound at week 0, 10, and 12. 3. Fatigue characteristics (questionnaires, rating of perceived exertion, lactic acid concentration) measured using questionnaires, verbal ratings, and Nova Biomedical Lactate Plus Meter at weeks 1-10, 12. |
| Overall study start date | 10/09/2024 |
| Completion date | 05/05/2026 |
Eligibility
| Participant type(s) | Healthy volunteer |
|---|---|
| Age group | Adult |
| Lower age limit | 18 Years |
| Upper age limit | 35 Years |
| Sex | Female |
| Target number of participants | 52 |
| Key inclusion criteria | 1. Young, healthy females aged 18-35 years 2. Must be able to maintain a habitual diet and perform resistance exercise two times per week throughout the trial 3. Must be able to perform exercise twice weekly 4. Able to begin exercise (assessed by Get Active Questionnaire) 5. Understand the study procedures and sign this form providing informed consent to participate in the study |
| Key exclusion criteria | 1. Pregnancy 2. Mild traumatic brain injury in the last year 3. Any history of severe traumatic brain injury 4. Cardiovascular conditions 5. Cerebrovascular conditions 6. Neurological conditions 7. Metabolic syndrome 8. History of syncope or light-headedness 9. History of migraines or chronic headache 10. Respiratory illnesses 11. Diabetes 12. Claustrophobia 13. Any current musculoskeletal injury that would make resistance exercise difficult or unsafe 14. History of psychosis 15. Eating disorders 16. Manic or bipolar disorder 17. Major psychiatric conditions 18. Dependence on alcohol or drugs within the past year 19. Use of medications known to affect protein metabolism, including: 19.1. Corticosteroids 19.2. Non-steroidal anti-inflammatory drugs (prescription or daily over-the-counter use) 19.3. Prescription-strength acne medications 20. Use of anabolic steroids or other banned performance-enhancing substances as outlined by the Canadian Center for Ethics in Sport |
| Date of first enrolment | 20/05/2025 |
| Date of final enrolment | 12/01/2026 |
Locations
Countries of recruitment
- Canada
Study participating centre
Hamilton
L8S 4L8
Canada
Sponsor information
University/education
The Office of the Vice-President, Research
Gilmour Hall, Room 208, McMaster University
Hamilton
L8S 4L8
Canada
| Phone | +1 (905) 525-9140 ext. 27270 |
|---|---|
| vprsrch@mcmaster.ca | |
"ROR" |
https://ror.org/02fa3aq29 |
Funders
Funder type
Research council
No information available
Results and Publications
| Intention to publish date | 01/06/2025 |
|---|---|
| Individual participant data (IPD) Intention to share | Yes |
| IPD sharing plan summary | Available on request |
| Publication and dissemination plan | Planned publication in a peer-reviewed journal |
| IPD sharing plan | The data-sharing plans for the current study are that all data will be made publicly available upon reasonable request from the PI, Dr. Baraa Al-Khazraji (alkhazrb@mcmaster.ca). |
Editorial Notes
23/07/2025: Trial's existence confirmed by Hamilton Integrated Research Ethics Board.
